DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Specification
The lengthy specification has not been checked to the extent necessary to determine the presence of all possible minor errors. Applicant’s cooperation is requested in correcting any errors of which applicant may become aware in the specification.
Information Disclosure Statement
The art submitted by Applicant has been considered by the Examiner in the same manner as other documents in Office search files are considered while conducting a search of the prior art in a proper field of search. Some of the art has been imported into SEARCH and filtered using keywords and other criteria in an attempt to determine if it is relevant. The art which cannot be imported into SEARCH has been considered by reviewing summary information, such as the title and abstract, in an attempt to determine if it is relevant.
Claim Rejections - 35 USC § 112 – Scope of Enablement
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
The following is a quotation of the first paragraph of pre-AIA 35 U.S.C. 112:
The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention.
Claims 1-20 are rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, because the specification, while being enabling for a limited scope based on the teachings in the application, does not reasonably provide enablement for the full scope recited in the claims. The specification does not enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the invention commensurate in scope with these claims.
MPEP 2164.08 states: “The Federal Circuit has repeatedly held that ‘the specification must teach those skilled in the art how to make and use the full scope of the claimed invention without ‘undue experimentation’.” In re Wright, 999 F.2d 1557, 1561, 27 USPQ2d 1510, 1513 (Fed. Cir. 1993).
Scope of the Claims and Teachings of the Application.
Claim 1 recites:
1. A method of in-service measurement of nonlinear interference on a per span basis in an optical network having a plurality of spans, the method comprising steps of:
varying power in a span of the plurality of spans to cause small power perturbations which do not impact traffic carrying signals;
observing a change in noise at an optical receiver at an end of the plurality of spans with the change due to the varying the power in the span; and
determining the nonlinear interference for the span based on the change in the noise.
This recites determining nonlinear interference “based on the change in noise”. In other words, the claim has a broad scope that includes any use of “change in noise” for determining NLI. Independent claim 11 is CRM having the functionality of claim 1, and has a similarly broad scope.
The application teaches how to measure per-span non-linear interference beginning at [0027]. The embodiments taught in the application are discussed below.
First Embodiment.
Section 1(a) teaches one embodiment beginning at [0036]. This embodiment teaches to measure the nonlinear interference by isolating the nonlinearity generated by the span under test. In particular, two VOAs are used, a first VOA before the span and a second VOA after the fiber span. This is illustrated in FIG. 2a. The first VOA is used to change the input signal power and the second VOA is used to compensate for the loss introduced by the first VOA (i.e., to keep the loss constant between amplifying sites). In particular, see:
[0036] In order to measure NLI per span, i.e., NSR.sub.NLI,k k=1˜K, we need to isolate the nonlinearity generated by the span under test from NSR.sub.imp,tot, NSR.sub.ASE,tot and NSR.sub.NLI,m (m≢k). The proposed approach can utilize two VOA's, one placed before and the other placed after the line fiber in each span. The VOA before the span under test, is used to change the input signal power into the fiber, thus NSR.sub.NLI,k will be changed. Concurrently, the second VOA after the span under test compensates for the change of loss introduced by the first VOA to keep the lost constant between the amplifying sites, all other elements in the link (amplifiers, spans that are not under test, etc.) will not experience a state change (power, gain, etc.) during the measurement of span k, hence NSR.sub.imp,tot, NSR.sub.ASE,tot and NSR.sub.NLI,m (m≢k) remain unchanged. Consequently, when performing the NLI measurement of span k, the change of NSR.sub.tot measured at the optical receiver is only due to the change of NLI at span k, i.e.,
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In other words, if the VOAs are controlled (or, if a method varies power) in the particular way taught above, then the change in total NSR measured at the receiver is only due to the change of NLI at a particular span k. See also:
[0037] Furthermore, the signal power of each channel at each span is known due to a combination of total power monitors, optical channel power monitors (OCM, also known as OPM), and other provisioning data allowing for accurate combined propagation models with backward error correction to determine power spectral information anywhere in the system. This model is described in PCT Patent Application No. PCT/US2021/40087, filed Jul. 1, 2021, and entitled “Utilizing an incremental noise metric for rapid modeling of optical networks,” the contents of which are incorporated by reference in their entirety. Therefore, when measuring span k, signal power at the input of the fiber after the first VOA can be denoted by:
[0038] At VOA state1: signal power is P.sub.S.sub.k
[0039] At VOA state2: signal power is Δα.sub.voa P.sub.S.sub.k, where Δα.sub.voa is the change in VOA transmission between VOA state1 and state2 in linear space.
[0040] Note again that when the VOA before span k changes by Advoa (in linear units), the VOA after span k will need to change by 1/Δα.sub.voa in order to keep total span loss constant. Since the power of nonlinear product changes cubically as the power of the signal, the NLI product generated at span k at the 2 VOA settings are denoted as: With VOAs in state1: Power of Nonlinear product is P.sub.NL,k,
[0041] With VOAs in state2: Power of nonlinear product is Δα.sub.voa.sup.3 P.sub.NL,k.
[0042] Therefore, Eq. (2) can be re-written as
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[0043] And since P.sub.s,k and Δα.sub.voa are known, P.sub.NL,k can be computed as
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[0044] and NSR.sub.NL,K at initial VOA setting (VOA setting 1), can be computed as
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In other words, the application teaches to determine NLI by measuring NSR when signal power at the input and output of each span is controlled in a particular way. The independent claims do not require VOAs or method steps controlling the power in a manner commensurate with the teachings of this embodiment, and the claims do not determine NLI as taught in this embodiment. Therefore, this teaching does not support the broad scope of the claim.
Second Embodiment.
Section 1(b) teaches another embodiment beginning at [0046] in which only a single VOA can be used at the output of an EDFA (see FIG. 2b). See:
[0046] The preceding subsection showed how a pair of VOAs located on either end of a transmission fiber can be used to isolate the nonlinear noise contribution from that fiber span. However, in some optical systems, there is only one VOA at the output of erbium-doped fiber amplifier (EDFA) to adjust the input power into the transmission fiber. There is not a VOA at the output side of the transmission fiber. However, we can still employ a similar approach where the VOA at the input of the transmission fiber under test is used to perturb the power entering a transmission fiber and the VOA at the input of the next span provides the compensating action. In the previous example VOAs on both ends of the span were used to ensure that the power entering the downstream amplifier remained constant. In this case the power perturbation will have a small impact on the noise characteristics of the downstream amplifier which will need to be accounted for with an amplifier model as described below.
In particular, this is a special case and it requires a particular amplifier model taught in [0047]-[0060].
[0047] The noise to signal ratio of the amplifier can be calculated as follows:
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[0048] where:
[0049] Lo.sub.s is the fiber span loss
[0050] h is Planck's constant
[0051] f is the channel center frequency
[0052] NF.sub.dB is the noise figure of EDFA at the end of span in dB unit.
[0053] G.sub.dB is the gain of EDFA at the end of the span in dB unit
[0054] B.sub.w is the channel bandwidth
[0055] P.sub.s,k was defined in section 1(a), which is the input power to the fiber
[0056] Therefore, the change in linear NSR can be obtained as:
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[0057] Here, we also share the same parameters as section 1(a). According to Eq. (3), the change in nonlinear NSR is as followed:
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[0058] The total variation in the NSR can be obtained by:
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[0059] As a result, nonlinear NSR at initial VOA setting can be computed as:
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[0060] where ΔNSRASE,k, can be calculated using Eq. (7). This technique allows per-span NLI estimates from networks in-service and where there is only one VOA.
In other words, the application teaches to determine NLI by measuring NSR when signal power at the output of each EDFA is controlled in a particular way. The independent claims do not require method steps controlling the power in a manner commensurate with the teachings of this embodiment, and the claims do not determine NLI as taught in this embodiment. Therefore, this teaching does not support the broad scope of the claim.
Third Embodiment.
Section 1(c) teaches another embodiment beginning at [0061] in which dithering is used to measure NLI. See:
[0061] The challenge of doing the above mentioned per span NLI measurement is to make sure the ΔNSRtot introduced by changing the VOAs of the span under test is small enough that it does not impact live traffic. Ideally, ΔNSRtot should be negligible from the receiver performance perspective and yet accurately quantifiable. Because the change in NSRtot resulting from the power perturbation is small compared with other noise sources in the transmission system it is difficult to accurately measure. Directly averaging the signal is ineffective because ΔNSRtot is also small compared with noise variations resulting from drifts in the system over the required averaging time. In order to address this challenge, we use phase sensitive detection where the power perturbation is dithered, and we estimate ΔNSRtot_test,i for each oscillation of the perturbation. By averaging over the change in NSR that is synchronous with the perturbation we can quantify the tiny change in ΔNSRtot.
In other words, this special case that uses phase sensitive detection and dithering of power perturbation, and in which the total change in NSR is estimated for each oscillation of the perturbation. The small changes in total NSR is measured by averaging over the change in NSR that is synchronous with the perturbation. This is discussed in more detail in [0062]-[0064].
[0062] We demonstrated this idea in a 10-span optical link, where the input power to span 9 is dithered by ±1dB, 200 times. An optical signal is transmitted over the 10-span optical link. The receiver measures NSRtot_Low when the input power of span 9 is set to the lower value, and it measures NSRtot_High when the input of span 9 is set to the higher value. ΔNSRtot is calculated immediately after each toggling and record as ΔNSRtot_test,i. After 200 cycles the averaged ΔNSRtot is calculated by
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[0063] where N=200. The obtained ΔNSRtot can then be used for calculating PNL,k and NSRNL,k, with Eq. (4) and Eq. (5) if the system has two VOA’s at both ends of each transmission fiber as described in section 1(a), or, the obtained ΔNSRtot can then be used for calculating PNL,k and NSRNL,k with Eqs. (7) - (10) if the system only has VOA’s at the inputs side of the transmission fibers.
[0064] The measurement results are shown in FIGS. 1A and 1B. FIG. 1A shows that both NSRtot_Low and NSRtot_High are noisy and the fluctuations are larger than the change caused by the perturbation. There is also a downward trend over the 200 tests. FIG. 1B plots ΔNSRtot_test,i over the 200 tests. The offset shown in FIG. 1B is the average value of ΔNSRtot_test,i (i=1~200), which is only 0.0115dB -- it means that the ±1dB dithering of the input power at span 9 of the 10-span system is negligible to the signal Rx performance. However, it enables accurate measurement of the small ΔNSRtot in a live system for per span NLI measurement.
In other words, the application teaches to determine NLI by measuring NSR when dithering of the power perturbation in a particular way. Although the independent claims recite “varying” the power, they do not clearly recite dithering the power perturbations as taught in this embodiment, and the claims do not determine NLI as taught in this embodiment. Therefore, this teaching does not support the broad scope of the claim.
The Dependent Claims.
The dependent claims add additional limitations but fail to address the issues raised with regard to the independent claims. As a result, the dependent claims also have a scope that would include steps that go beyond the teachings of the present application.
The Claims do not Recite the Particular Structure, Materials, or Steps.
As discussed above, the application teaches how to make and use the invention using particular structure and steps to implement the determining of NLI based on noise. As also discussed above, the claims recite the desired functionality/results, but do not recite the particular structure and steps that accomplish the claimed functionality/results. This results in claims having a scope that is much broader than the teachings of the application.
When considering the teachings of the application and the scope of the claims, as discussed above, see MPEP 2173.05(g), 4th paragraph:
… Further, without reciting the particular structure, materials or steps that accomplish the function or achieve the result, all means or methods of resolving the problem may be encompassed by the claim. Ariad Pharmaceuticals., Inc. v. Eli Lilly & Co., 598 F.3d 1336, 1353, 94 USPQ2d 1161, 1173 (Fed. Cir. 2010) (en banc). Unlimited functional claim limitations that extend to all means or methods of resolving a problem may not be adequately supported by the written description or may not be commensurate in scope with the enabling disclosure, both of which are required by 35 U.S.C. 112(a) and pre-AIA 35 U.S.C. 112, first paragraph. In re Hyatt, 708 F.2d 712, 714, 218 USPQ 195, 197 (Fed. Cir. 1983); Ariad, 598 F.3d at 1340, 94 USPQ2d at 1167. …
This supports a finding that the broad scope of the claims may not be commensurate with the teachings in the disclosure.
No Teaching of a General Case for the Full Scope of the Claims.
The Examiner also notes that there is no teaching of a method or CRM with the broad scope recited in the claims. In particular, there is no teaching of a general case that can determine NLI “based on” the change in the noise without being limited to special cases and without requiring any particular operations or calculations other than using the change in the noise (i.e., any operation using the change in noise determines the NLI).
If such a general case were contemplated or discovered by the inventors, its disclosure and a description of its operation would be expected as part of the application in order to support broad claims, such as claim 1 and 11. This is particularly true because, as discussed above, the embodiments that are disclosed in the application require fairly complex and particular operations/algorithms used with particular structures. These operations/algorithms would be unnecessary if a general case had been known by the inventors, and yet the application does not include a disclosure of the general case. This supports a conclusion that the scope of the claims is not commensurate with the teachings of the application.
Opportunity to Amend.
See also MPEP 2111, 4th paragraph:
Because applicant has the opportunity to amend the claims during prosecution, giving a claim its broadest reasonable interpretation will reduce the possibility that the claim, once issued, will be interpreted more broadly than is justified. In re Yamamoto, 740 F.2d 1569, 1571 (Fed. Cir. 1984); In re Zletz, 893 F.2d 319, 321, 13 USPQ2d 1320, 1322 (Fed. Cir. 1989) (“During patent examination the pending claims must be interpreted as broadly as their terms reasonably allow.”); In re Prater, 415 F.2d 1393, 1404-05, 162 USPQ 541, 550-51 (CCPA 1969) … See also In re Morris, 127 F.3d 1048, 1054-55, 44 USPQ2d 1023, 1027-28 (Fed. Cir. 1997) (The court held that the PTO is not required, in the course of prosecution, to interpret claims in applications in the same manner as a court would interpret claims in an infringement suit. Rather, the “PTO applies to verbiage of the proposed claims the broadest reasonable meaning of the words in their ordinary usage as they would be understood by one of ordinary skill in the art, taking into account whatever enlightenment by way of definitions or otherwise that may be afforded by the written description contained in applicant’s specification.”).
Therefore, if Applicant intends the claims to have a scope that is narrower than the broadest reasonable interpretation, the claims should be amended during prosecution to provide the intended scope.
Other Wands Factors.
The direction and examples provided by the inventor(s) appear to be enabling for a limited scope of the invention (i.e., the embodiments of Sections 1(a)-1(c)), but not for the full scope of the claims.
The nature of the invention is optical transmission and reception apparatuses and methods. The components used in the various embodiments were known to one of ordinary skill (e.g., optical transmitters and receivers, optical spans, VOAs, EDFAs, and signal processors). However, the nature of the invention is not these components, which are merely the basic building blocks used for all forms of different optical devices. The nature of the invention is optical communications equipment arranged to allow for the measurement of NLI on a per-span basis in an optical system with plural spans, and specifically the particular selection, arrangement, interconnection, and operation of components that form that equipment in a useful way to produce the desired results.
Similarly, one of ordinary skill would also know how to perform other tasks in the present technological area and related to the invention, such as providing power to components (although power supplies and power specifications are not explicitly taught in the application), and splicing/coupling the electrical and optical components together (although this is not explicitly taught in the application), and managing the temperature of electrical and optical components which are susceptible to performance degradation and undesirable operational variations based on temperature (although this is not explicitly taught in the application), and shielding components from EM interference that can be generated by such devices (although this is not explicitly taught). Although this is not an exhaustive list, the obvious modifications based on the disclosure and the knowledge of one or ordinary skill are nonetheless of a limited scope.
However, these modifications do not address the issues raised above regarding the disparity between the scope of the claims and the teachings of the application.
Experimentation.
As discussed above, the claims include many possible operations/algorithms and the application does not teach the full scope of the claims. Furthermore, there is no reasonable expectation that all possibilities within the scope of the claims will produce the desired results or functions. As a result, if one of ordinary skill were to attempt to make and use the full scope of the claims, it would require making, testing, or otherwise evaluating all (or at least a very large number of) possible combination of operations/algorithms within the scope of the claims to find what works to perform the claimed functionality. This results in a practically unlimited number of embodiments that would need to be made, tested, or otherwise evaluated to determine which embodiments within the scope of the claims are operative and which are inoperative. In other words, would require almost infinite experimentation in order to make and use the full scope of the claims.
This supports a finding that undue experimentation would be required to make and use the full scope of the claims.
Conclusion.
After careful consideration the Examiner has concluded that the specification does not enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the invention commensurate in scope with these claims. In other words, the specification fails to teach those skilled in the art how to make and use the full scope of the claimed invention without ‘undue experimentation’.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
US 2020/0313380 (Fei) is the closest art of record and at FIG. 7 illustrates an optical system including an ASE source 70, plural optical spans, a receiver to receive the transmitted signals, and a processor to control functionality.
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See, for example:
[0004] In an embodiment, a system includes a processor communicatively coupled to an Amplifier Stimulated Emission (ASE) source and an optical receiver, wherein the processor is configured to cause transmission of one or more shaped ASE signals, from the ASE source, on an optical fiber, obtain received spectrum of the one or more shaped ASE signals from the optical receiver connected to the optical fiber, and characterize the optical fiber based in part on one or more of a nonlinear skirt and a center dip depth in the received spectrum of the one or more shaped ASE signals. The one or more shaped ASE signals can be formed by the ASE source communicatively coupled to a Wavelength Selective Switch (WSS) that is configured to shape ASE from the ASE source to form the one or more shaped ASE signals with one or more peaks and with associated frequency. The one or more shaped ASE signals can have two distinct peaks at the transmission with a significant dip at a center frequency, and the received spectrum of the one or more two-peak ASE signals has much less of a dip that the center dip depth. The processor can be further configured to determine a fiber type based on a signature of the one or more of the nonlinear skirt and the center dip depth in the received spectrum of the one or more shaped ASE signals. The optical fiber can be characterized to determine chromatic dispersion, β.sub.2, and fiber nonlinear coefficient, γ.
In particular, the optical receiver characterizes the optical fiber based on nonlinear skirt and center dip depth in the received spectrum of the ASE signals. Furthermore, the ASE signal is shaped by the WSS. From this, the processor can determine the fiber type.
It also teaches to vary power using amplifiers (e.g., EDFAs). See, for example, the amplifiers in FIG. 7 and see:
[0038] The OADM nodes 52, 54 include a Wavelength Selective Switch (WSS) 62 that faces the optical fibers 58, 60. The WSS 62 forms an optical degree that faces the optical fibers 58, 60. In this example, a single degree is illustrated at each of the OADM nodes 52, 54. Of course, practical implementations may include multiple degrees, each facing a different optical section 50. The WSS 62 is configured to add/drop spectrum to/from the degrees and/or locally. Each OADM node 52, 54 includes a post-amplifier 64 on the transmit side and a pre-amplifier 66 on the receive side. The amplifiers 64, 66 can be Erbium-Doped Fiber Amplifiers (EDFAs). Also, Raman amplifiers may be used as well in addition to EDFAs. The OADM nodes 52, 54 also include an Optical Channel Monitor (OCM) 68 (a.k.a. Optical Power Monitor (OPM), etc.) which is an optical receiver connected (e.g., by a tap) to an output of each of the amplifiers 64, 66. The OCM 68 can have two receivers to simultaneously monitor each of the optical fibers 58, 60 or a switch to allow a single receiver to monitor one of the optical fibers 58, 60 at a time.
See also FIG. 8, steps 106 and 118 which teach to used EDFAs to vary power in the various spans. See also steps 104 and 116 which teach to step through each span.
[0043] For every span i=1˜N in the optical section, starting with i=1 (step 104), the measurement process 100 includes setting the optical amplifiers in a power mode for all spans (this power mode setting only needs to be done once, not necessarily for each iteration) and setting signal launching power at a reference power level, P0.sub.ref for span i, for example P0.sub.ref=15 dBm, and setting the rest of the spans at a much lower launching power, for example (P0.sub.ref−15) (step 106). The measurement process 100 includes reading the OPM 68 at the downstream OADM, and recording the center dip depth of the received signal as Depth.sub.ref|.sub.span=i (step 108). The span count is incremented and steps 104-110 are repeated until the end of the section (step 110).
[0044] The signal broadening effect characterized by Depth.sub.ref|.sub.span=i is mainly generated by span i with high signal launching power. The purpose of steps 104-110 is to find the launching power for every span to yield the center dip depth around an optimum center dip depth, Depth.sub.opt. Depth.sub.opt is found when the PSD of the nonlinear product at the center gap is much higher than line EDFA ASE noise, while the corresponding in-band nonlinear product is still negligible compared to the signal. Depth.sub.opt depends on the width of the signal and the gap of the two peaks. For example, when both the signal and gap width is 50 GHz, Depth.sub.opt=15 dB. Since the absolute level of Depth changes twice as fast as P0, the launching power for span i=1˜N is computed by
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…
[0046] For every span i=1˜N in section (step 116), the measurement process 100 includes setting the optical amplifiers in power mode for all spans (this power mode setting only needs to be done once, not necessarily for each iteration), and setting launch power of span i to P0|.sub.span=i, such that the center dip depth due to the signal broadening effect of span i is around the pre-defined Depth.sub.opt. For the rest of the spans j=1˜N, j≠i, set launch power to
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However, it fails to teach any of the particular implementations described in the present application (e.g., see the discussion of the teachings of the present application under the 112(a) rejections).
US 4,628,278 (Bottman) at FIG. 3 illustrates a non-inverting amplifier followed by an attenuator, followed by a second, identical non-inverting amplifier.
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See the description of FIG. 3 in col. 3; see col. 5, lines 58-62:
Referring now to FIG. 3, the case of an amplifier followed by an attenuator followed by an identical amplifier is shown in block form, which represents the mathematical model of such case. It is assumed that the two amplifiers are substantially the same …
Eqn I is a transfer function for the amplifier including both first and second order terms. Eqn VI illustrates a linear transfer function for the attenuator. FIGS. 4 and 11 illustrate the use of inverting amplifiers with a non-inverting attenuator.
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See also Bottman at col. 8, lines 38-44:
… the amplifiers of the present invention must: (1) each have gain (in dB) equal to the attenuator's loss (in dB); (2) each be substantially identcal; and (3) each be inverting. All three of these conditions must be met in order for the present invention to provide the low level D.C. and even-order harmonic distortion characteristic.
While this teaches the general structure of the present application, including the use of amplifiers and attenuators associated with spans of an optical link, it is directed to compensating for non-linearities, not measuring non-linear interference on a per-span basis.
US 2006/0193638 (Akiyama) at FIG. 7 illustrates a portion of an optical system including plural links with amplifiers at the beginning and end of each link.
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Akiyama teaches to measure and compensate for dispersion. See, for example:
[0009] Here, the amount of wavelength dispersion compensation has a tolerance in a transmission section (path) of each transmission signal, and the difference between the amount of wavelength dispersion of the transmission section and the amount of wavelength dispersion compensation that is within the tolerance is made into a tolerable residual dispersion range. That is, a signal transmission at a guaranteed transmission characteristic is attained by designing the network so that wavelength dispersion may fall within the tolerable residual dispersion range (the amount of wavelength dispersion is compensated for so as to be within the tolerable residual dispersion range).
[0061] Next, the first embodiment is described, wherein a wavelength dispersion compensation design is performed for a link that is extracted from an optical network as shown in FIG. 6. Here, the extracted link is from a node N10 (point A) to a node N13 (point B) as indicated by a thick line. The extracted link consists of three spans P11, P12, and P13 that connect the starting node N10 and the terminating node N13, and nodes N11 and N12 that are each equipped with OADM functions as shown in FIG. 7.
[0092] For example, suppose that the required amount Dd(i) of the wavelength dispersion compensation of a certain Path (i) is -545 ps/nm <Dd(i) <-515 ps/nm. Usually, the dispersion compensators are adjustable in steps of 50 ps/nm.or 100 ps/nm. Then, according to the present embodiment, the dispersion compensators are made capable of being adjusted in steps of 25 ps/nm. Thus, the smaller step can provide a solution to the inequalities.
It also teaches to determine a different value of dispersion compensation. See, for example:
[0092] For example, suppose that the required amount Dd(i) of the wavelength dispersion compensation of a certain Path (i) is -545 ps/nm <Dd(i) <-515 ps/nm. Usually, the dispersion compensators are adjustable in steps of 50 ps/nm.or 100 ps/nm. Then, according to the present embodiment, the dispersion compensators are made capable of being adjusted in steps of 25 ps/nm. Thus, the smaller step can provide a solution to the inequalities.
In other words, the DCMs are adjusted to change their dispersion compensation values in order to achieve a desired dispersion compensation value (e.g., a achieve a dispersion compensation value within the desired range).
Any inquiry concerning this communication or earlier communications from the examiner should be directed to DARREN WOLF whose telephone number is (571)270-3378. The examiner can normally be reached Monday through Friday, 6:00 AM to 2:00 PM.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, KENNETH N. VANDERPUYE can be reached on 571-272-3078. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/DARREN E WOLF/Primary Examiner, Art Unit 2636
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